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The mountain plover (Charadrius montanus) is a member of the group of birds called shorebirds that are usually found along the edges of water areas. It is an unusual shorebird since it spends its entire life avoiding water. The mountain plover is a Great Plains native that breeds on the arid shortgrass prairie from northern Montana to southern New Mexico and winters in California, Texas and Mexico. Since 1837, it has been reported from 23 states, Canada and Mexico. The number of mountain plovers has declined drastically in the last century. About 1900. it was abundant and was heavily market hunted in California and probably throughout its range. As early as 1914, plover numbers were reported to be declining. The Migratory Bird Treaty Act of 1916 protected the plover from hunting, but its range and numbers continued to decrease. Recent studies have estimated a 50 percent to 89 percent reduction in mountain plovers.
Current distribution maps are misleading, showing plovers occurring over a large range. In reality, habitat within this range is limited. Breeding strongholds are confined to small areas of native prairie in Montana and Colorado. Most of the birds winter in California, principally in the San Joaquin Valley, an area experiencing high rates of human population growth. Today the mountain plover is considered endangered in Canada, a species of special interest or concern in Montana and Oklahoma, extirpated in North Dakota and South Dakota, on the watch list in Kansas and threatened in Nebraska. The U.S. Fish and Wildlife Service is considering listing the mountain plover as endangered or threatened throughout its range.
The earliest records of the mountain plover in Nebraska are from territorial surveys conducted in the 1850s. A survey party collected an egg at the North Fork of the Platte River, 120 miles west of Fort Kearny. The species would never again be reported that far east in Nebraska. Until the early 1900s, mountain plovers were common summer residents in the Nebraska Panhandle, but since then there have been only scattered observations. Most recent sightings are of adults in Kimball and Box Butte counties, but there are two accounts of breeding, one of adults with young and one of an adult on a nest. The limited information available suggests the mountain plover occurs rarely and locally in the state. It was listed as threatened in Nebraska in 1976.
While in Nebraska the mountain plover can be seen in its breeding plumage. It looks much like a pale version of the more common killdeer, but without chest stripes. The head, back, wings and portions of the upper breast are a pale, sandy brown. The neck and underparts are white. The crown is capped with black, and a black stripe extends from the base of the beak to the eye. The dark bands contrast sharply with the brilliant white forehead and throat. The bill is black and the legs are fairly long and pale brown or brownish-yellow. In flight, the best field marks are a thin white wing stripe and black tail band fringed with a white border. Wintering plumage is pale and the dark head bands are absent. Males and females are similar in size and color.
Little information describing mountain plover migration is available. Shorebirds are strong flyers and often cover several hundred miles a day. The mountain plover may cover distances of 800 to 1,000 miles on its migration between breeding and wintering areas. Fall flocking begins as early as July, with birds leaving the breeding grounds by August and arriving on the wintering grounds in early November. They depart from the wintering grounds in mid-March and arrive or. breeding grounds a few days later.
When approached, a mountain plover is more likely to crouch or walk away than to fly. If disturbed, a bird may move a few steps then stop abruptly, standing silent and motionless. When forced to fly, it rises rapidly with quick wing beats flying low over the ground. Plovers can be difficult to see because of their cryptic coloration and behavior.
Mountain plovers arrive on the breeding grounds in small flocks. Males commonly reoccupy their former territories, which they defend against intrusion by other males. Territorial males perform aerial displays to attract a mate, flying to a height of 15 to 30 feet, holding their wings up over the back in a deep V, then floating back to the ground in what is called the falling leaf display. A call consisting of a series of "wee-wee-wee" sounds begins at the apex of the flight and continues until the bird reaches the ground. Both sexes perform the falling leaf display, but females perform it only after mating. Females frequently return to the same area each year, but visit the territories of several males before selecting a mate. During courtship, several nest scrapes are made before one is eventually chosen for a nest.
The nest consists of a shallow depression in the ground lined with a small amount of materials found nearby. Nests are often next to conspicuous objects such as cow chips.
Mountain plovers usually lay three well-camouflaged eggs that are dark olive with black markings. Only one adult attends the nest, rotating the eggs and shading them on hot days during the 29-day incubation. Some evidence suggests that a female produces one clutch of eggs for her mate to attend and then produces a second clutch about two weeks later which she attends.
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